Monoclonal anti-IgA antibody expression in the posterior commissure mucosae of laryngeal cancer patients

Department of 1,4Otolaryngology, 2Pathology, Kasr El Aini Hospital, Cairo Medical School, 3Biostatistics and Epidemiology Department, National Cancer Institute, Cairo University, Egypt. ABSTRACT Objective: It has been reported that the interarytenoid fold of the larynx (IAFL) is rarely affected by malignancy 1. It is therefore crucial that research be undertaken to delineate its structural differences of the posterior commissure of the larynx from other laryngeal sub-sites. Study Design: Comparing the expression of anti-IgA antibody in laryngeal tumor cells and the mucosa of the PC (free of tumor). The study aims to detect a specific immune response mounted by the host that might explain the previous observation. Setting: Twenty-seven specimens from patients suffering from T3 and T4 squamous cell carcinoma were included in the present study. Patients and Methods: Sample biopsies were procured from the tumor, the PC, and the tumor-free mucosae of the larynx, and were subjected to immunohistochemical study using a commercially prepared rabbit-hosted monoclonal antiIgA antibody. Several criteria were applied to evaluate the expression of IgA in all of the samples. Results: The posterior commissure was free of tumor involvement in all twenty-seven of the excised larynges. IgA expression was significantly higher in the PC epithelium than in the neighboring laryngeal epithelium devoid of tumor. One interesting result is the highly significant expression of IgA in the immunocytes located in the PC as compared to those in the tumor, where it is almost negligible. Conclusion: Immunohistochemical study further revealed a significant characteristic of the PC regarding its higher expression of IgA. Research should be directed toward revealing the factors that provide immunity and resistance in the PC area.